Wire spring anb spring structure



March 28, 1944. J. KRONHEIM 1 WIRE SPRING AND SPRING STRUCTURE Original Filed May 24, 1938 IN VENTOR.

73 7503 KRONHE/M f Irma.

Reiuued Mar. 28, 1944 J acob Kronheim,

Original No. 2,250,486, No. 209,713, May 24,

issue December 26, 1941,

Claims.

This invention relates to flat springs of sinuous or similar shape, used for seats of upholstered furniture, cushioned automobile seats or the like, and more particularly to the type of springs described in Patent, No. 2,047,411, dated July 14, 1936. Springs of this type embody an upper axially compressible and extensible seating portion, a yielding, rearwardly and downwardly'extending supporting means at the front end of the seating portion, and a downwardly extending yielding supporting means at the rear end of the seating portion. The supporting means of the springs are either integrally formed with the seating portion or rigidly connected to the opposite ends thereof to effect upward bulging and longitudinal stretching of the seating portion when a load is placed thereon.

These springs are assembled to spring structures by individually mounting the springs with their supporting means upon opposite rails of an open frame so that all seating portions of the springs are situated in a plane above the frame, and by interconnecting all seating portions of the springs to a continuous seating surface, generally to be covered with padding and upholstering material and a customary roll front edge so as to insure proper mounting and holding of loose seat cushions.

As well known, construction of a roll edge and its attachment to a seating surface is a slow and costly process which necessitates employment of highly skilled labor.

The principal object of the present invention is to reduce manufacturing and labor costs in building of upholstered furniture by providing springs of improved construction and design embodying at their front seating portions elevated means substantially equal in action to that of a front roll edge.

Another object of the invention is the provision of an improved wire spring having an elevated seating portion and integral elevated means at the front of the seating portion equal in action to that of a front roll edge.

,In addition, the invention has certain other marked superiorities which radically distinguish it from presently known structures. The improvements or superior characteristics embodying certain novel features of construction are clearly set forth in the following specification and the appended claims; and a preferred form of embodiment of the invention is hereinafter shown with reference to the accompanying drawing forming part of the specification.

Cleveland Heights, Ohio, assignor to John 0. Lincoln,

Scottsdale, Ariz.

dated July 29, 1941, Serial 1938. Application for re- Serial No. 424,537

In the drawing:

Fig. 1 shows a vertical sectional view through a spring structure mounted in the open frame of a cushioned seat, the spring structure embodying springs provided with an elevated front edge to I permit of proper support of seat cushions'on the padded spring structure without use of a special front roll edge; the section being taken on line |-i of Fig. 2.

Fig. 2 is a cross section-a1 view through the spring structure and chair base shown in Fig. 1, the section being taken on line 2-2 of Fig. 1.

Fig. 3 is a fragmentary vertical sectional view through the rear portionof the chair base and spring structure shown in Fig. 1, the section being taken on line 3-3 of Fig. 2.

Fig. 4 is a perspective view of one of the springs used in the construction of the spring structure shown in Fig. 1; and

Fig. 5 is a [perspective view of one of the spring hooks yieldingly tying the rear end of the spring structure to the rear rail of the open frame.

Referring now more particularly to the drawing, reference numeral 2 represents the frame of a chair embodying at its bottom portion a rectangular open frame 3, the front, rear and side rails 4, 5 and 6 of which are secured to the front and rear legs I and 8 of the frame 2. Open frame 2 has mounted on its front and rear rails l and 5 a plurality of flat springs 9, made of sinuous-shaped or horizontally corrugated steel wire. These springs each include rearwardly and downwardly inclined front and rear supporting means or lever arms Ill, II respectively, adapted to support the proper seating portion I2 of e spring in an elevated position, which support ng means extend from the opposite ends of the said seating portion. The front supporting means or supporting arm i0 is looped at its free end to form two oppositely wound coils H and I5, arranged in a plane substantially rectangular to the plane of the seating surface l2, which coils are of different elasticity, coil I having less windings than coils l5 and therefore being stiffer than said latter coil. lever arm I0 is bent and offset as at It to prohibit contact of the coils l4 and IS with the seating portion l2 when a load is placed upon said. portion. The free end of coil i5 is extended for- I1 being used for such purpose.

The rear supporting means i portion I2 is formed as a curved I for the seating extension oi said surface, curved at its rear portion to semi-circu- Preferably, as shown, front a substantial reduction lar shape. This rear supporting means has its free end looped to two oppositely wound coils I I and I 9. arranged in a plane substantially rectangular to the plane of the seating portion. The coils I l and I9 are also of din'erent elasticity, coil it having less windings than coil I! and therefore being stifl'er than said latter coil. The free end of coil II is'extended rearwardly and shaped to a hook 20, adapted to engage with th rear rail Ii for supporting the rear supporting means II on said rail and connecting it thereto, which hook 20 is held in proper position on rail I by staples 2 I.

The above described construction of the rear supporting means I I of the spring 8 materially simplifies manufacturing of said spring and is of great importance for spring seat structures in which the seating terconnected to a substantially unitary seating surface 22 by means of an edge wire 23 and wire braces 24, which wires are secured to the springs by-clips 25, all as shown in the drawing. In such spring seat structure the movement of the seating-surface is mainly "controlled by the rear supporting means which in the describedconstruction has rather low resistance against forward movement of the seating surface when under load. This deficiency in the structure is overcome by the arrangement of torsion spring means 26 which pivotally engage a rearward extension 21 of the edge wire 23 and are secure to the rear rail by means of staples 28. The torsion spring means 26 are made of spring steel wire and embody a coiled portion 29, having extended from its opposite ends a hook-shaped lever arm 3|! and an angular resting and attachment arm which latter is secured to the rail 5 in a manner previously described.

The coil I5 of the front supporting means and the coil I! of the rear supporting means eflect of the forward movement of the structure under load. Thus coil II has less resiliency than coil I5, and coil I8, having less resiliency than coil II, permit of the coils I5 and I 8 being contracted to eil'ect a substantially vertical downward movement of the seating surface when a load is placed thereon until the elasticity of these coils approaches that of the coils I4 and I8, whereafter all coils cooperate in the, forward and downward movement of the seating surface under load. Such action of a spring seat structure is desirable, as it softens the seating surface of the spring structure and makes seating on the structure more comfortable without decreasing its efliciency in carrying heavy loads. a

Spring structures of the type described are generally padded and have their front edge provided with a roll edge to give proper support to -the legs of a person sitting on such structure and to properly support the customary seat cushions in such a fashion that the cushions do not slip from their support. The present spring structure embodies means which permit of discarding the portions of all springs are inbodying an elongated,

edge roll to facilitate manufacturing at deceased cost. For that purpose the front part of the seating portions I2 of all springs I are in the front of the spring structure.

Having thus described my invention:

What I claim is:

1. A spring for cushioned seats or the like com. prising a horizontally corrugated seating portion including at its front end a ledge upwardly and outwardly inclined with respect 7 to the axis of saidseating portio a front supporting means respect thereto, and rear supporting means integrally extended from the rear end of said seating portion.

2. A spring for cushioned seats or the like comprising a horizontally corrugated seating portion including at its front end a corrugated ledge upwardly and outwardly inclined with respect to the axisof said seating portion, and inclined front and rear supporting means integrally extended from said seating portion at an inclination with respect thereto. 1

3. A spring for cushioned seats or the like, comprising an elongated, corrugated body portion having its one end portion upwardly and outwardly inclined to oilset a part of said body portion, so that said body portion will readily follow the curved contour of the load applied in use to the spring when such spring is mounted on a frame, and yielding supporting means for said body portion extended inwardly and downcorrugated body portion.

4. A spring for cushioned seats or the like, em-

corrugated body portion having its one end portion upwardly and outrugat'ed body portion when the spring is mounted on a frame and loaded, and a V-shaped supporting means extending at a sharp angle rearwardly and downwardly from the said-one end portion of said body portion.

5. A spring for cushioned seats or the like, embodying an elongated, corrugated and upwardly curved body portion having its one end portion upwardly and outwardly inclined to ofiset a part of said body portion and curving the body portion near said end portion downwardly in a direction opposite to the upward curvature. of said body portion to facilitate downward bulging of the body portion when the spring is secured to a frame and loaded, and a V-shaped supporting means extending at a sharp angle rearwardly and downwardly from the said one end portion of said body portion.

JACOB KRONHEIM. 

